/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.hotswap.agent.util.spring.path;

import java.util.Comparator;
import java.util.Map;

/**
 * Strategy interface for {@code String}-based path matching.
 *
 * <p>
 * Used by
 * {@link org.hotswap.agent.util.spring.path.springframework.core.io.support.PathMatchingResourcePatternResolver}
 * , {@link org.springframework.web.servlet.handler.AbstractUrlHandlerMapping},
 * {@link org.springframework.web.servlet.mvc.multiaction.PropertiesMethodNameResolver}
 * , and {@link org.springframework.web.servlet.mvc.WebContentInterceptor}.
 *
 * <p>
 * The default implementation is {@link AntPathMatcher}, supporting the
 * Ant-style pattern syntax.
 *
 * @author Juergen Hoeller
 * @since 1.2
 * @see AntPathMatcher
 */
public interface PathMatcher {

    /**
     * Does the given {@code path} represent a pattern that can be matched by an
     * implementation of this interface?
     * <p>
     * If the return value is {@code false}, then the {@link #match} method does
     * not have to be used because direct equality comparisons on the static
     * path Strings will lead to the same result.
     * 
     * @param path
     *            the path String to check
     * @return {@code true} if the given {@code path} represents a pattern
     */
    boolean isPattern(String path);

    /**
     * Match the given {@code path} against the given {@code pattern}, according
     * to this PathMatcher's matching strategy.
     * 
     * @param pattern
     *            the pattern to match against
     * @param path
     *            the path String to test
     * @return {@code true} if the supplied {@code path} matched, {@code false}
     *         if it didn't
     */
    boolean match(String pattern, String path);

    /**
     * Match the given {@code path} against the corresponding part of the given
     * {@code pattern}, according to this PathMatcher's matching strategy.
     * <p>
     * Determines whether the pattern at least matches as far as the given base
     * path goes, assuming that a full path may then match as well.
     * 
     * @param pattern
     *            the pattern to match against
     * @param path
     *            the path String to test
     * @return {@code true} if the supplied {@code path} matched, {@code false}
     *         if it didn't
     */
    boolean matchStart(String pattern, String path);

    /**
     * Given a pattern and a full path, determine the pattern-mapped part.
     * <p>
     * This method is supposed to find out which part of the path is matched
     * dynamically through an actual pattern, that is, it strips off a
     * statically defined leading path from the given full path, returning only
     * the actually pattern-matched part of the path.
     * <p>
     * For example: For "myroot/*.html" as pattern and "myroot/myfile.html" as
     * full path, this method should return "myfile.html". The detailed
     * determination rules are specified to this PathMatcher's matching
     * strategy.
     * <p>
     * A simple implementation may return the given full path as-is in case of
     * an actual pattern, and the empty String in case of the pattern not
     * containing any dynamic parts (i.e. the {@code pattern} parameter being a
     * static path that wouldn't qualify as an actual {@link #isPattern pattern}
     * ). A sophisticated implementation will differentiate between the static
     * parts and the dynamic parts of the given path pattern.
     * 
     * @param pattern
     *            the path pattern
     * @param path
     *            the full path to introspect
     * @return the pattern-mapped part of the given {@code path} (never
     *         {@code null})
     */
    String extractPathWithinPattern(String pattern, String path);

    /**
     * Given a pattern and a full path, extract the URI template variables. URI
     * template variables are expressed through curly brackets ('{' and '}').
     * <p>
     * For example: For pattern "/hotels/{hotel}" and path "/hotels/1", this
     * method will return a map containing "hotel"->"1".
     * 
     * @param pattern
     *            the path pattern, possibly containing URI templates
     * @param path
     *            the full path to extract template variables from
     * @return a map, containing variable names as keys; variables values as
     *         values
     */
    Map<String, String> extractUriTemplateVariables(String pattern, String path);

    /**
     * Given a full path, returns a {@link Comparator} suitable for sorting
     * patterns in order of explicitness for that path.
     * <p>
     * The full algorithm used depends on the underlying implementation, but
     * generally, the returned {@code Comparator} will
     * {@linkplain java.util.Collections#sort(java.util.List, java.util.Comparator)
     * sort} a list so that more specific patterns come before generic patterns.
     * 
     * @param path
     *            the full path to use for comparison
     * @return a comparator capable of sorting patterns in order of explicitness
     */
    Comparator<String> getPatternComparator(String path);

    /**
     * Combines two patterns into a new pattern that is returned.
     * <p>
     * The full algorithm used for combining the two pattern depends on the
     * underlying implementation.
     * 
     * @param pattern1
     *            the first pattern
     * @param pattern2
     *            the second pattern
     * @return the combination of the two patterns
     * @throws IllegalArgumentException
     *             when the two patterns cannot be combined
     */
    String combine(String pattern1, String pattern2);

}